Modern shipping containers are subjected to rough handling and must be waterproof or water resistant and built to withstand dropping, impact with other containers, and other adverse shipping conditions without transmitting the shock to the equipment or product packed inside. This is particularly true for containers used to ship delicate or shock-sensitive transportable electronic equipment.
Such containers are ideally opened and closed quickly and easily using fasteners which provide both a strong and effective closure of the container and which are not subject to accidental opening. Such fasteners should be able to seal the cover of the container down against the body of the container, or down against a seal between the cover and the body to prevent the penetration of liquids into the interior. Further, such a fastener should be contained as much as possible inside the container in order to protect the latching mechanism from adverse shipping conditions. Finally, such a fastener should be reliable and not subject to accidental opening while the container is in transit.
While many existing shipping containers have latching mechanisms which meet some of these criteria, they do not meet all of the criteria. For example, U.S. Pat. No. 330,986 discloses a box fastener which uses a screw bolt to hold a fastening strip in place, holding the cover of a box down after the fastening strip has engaged an inner lip on the cover of the box and the cover has been closed. Although this "latching mechanism" is largely contained within the box, it does not pull the cover down against the box to seal the container from the entry of, for example, liquids. Further, opening and closing the cover on this type of box is tedious and would likely require a special tool such as a wrench for rotating the bolt into or out of a threaded plate.
Similarly, U.S. Pat. No. 2,269,264 discloses a latching mechanism in which a captive screw is rotated to rotate a latch into position and then to pull the latch on the inside against a wall, closing the cover against the wall. In such a structure, a special tool such as a screw driver is required to close and lock the cover. Further, repeated uses subject the threads of the captive screw to stripping.
U.S. Pat. Nos. 2,961,265 and 3,510,162 provide latching mechanisms which are disengaged to open by pulling out on a handle. Such mechanisms are totally unsuitable for shipping containers, since the external handles could be snagged, causing accidental opening of the container in transit.
Thus, the need exists for a latching mechanism for modern reusable shipping containers which is easy to use, reliable, not subject to accidental opening, which can be contained on the inside of the container, but which can be operated from outside the container without the use of special tools, and which can provide sufficient sealing force to exclude unwanted liquids, dust or other contaminants from the interior of a shipping container.